It is sometimes necessary, or otherwise desirable, to remove unwanted materials disposed within a bodily passage. For example, lithotripsy—the disruption and removal of calculi, or stones, from a region of the body—is frequently performed to remove stones disposed in a salivary duct or the urinary tract.
Various types of lithotripsy are known, including shockwave lithotripsy, extracorporeal shockwave lithotripsy, laser lithotripsy, percutaneous lithotripsy, endoscopic lithotripsy, and pneumatic lithotripsy. In pneumatic lithotripsy, a probe attached to a firing handle is advanced through a previously placed sheath, or the working channel of a scope, until the distal end of the probe contacts a stone disposed in a bodily passage. The firing handle is activated to rapidly advance the probe to produce an impact between the distal end of the probe and the stone causing its fragmentation and enabling its removal.
Pneumatic lithotripsy can be challenging in relatively small body passages, such as the salivary ducts and urinary tract, due to the deficiencies of probes that utilize a continuous outer diameter. Such probes prevent lithotripsy from being performed in small bodily passages when the probe has a large outer diameter and increase the tendency of the probe to kink along its length when the probe has a small outer diameter. Moreover, probes having a small outside diameter reduce the capacity of the probe to transmit power along its length.
In addition, current probes fail to provide a mechanism that allows a user to have fine motor control over the probe while performing lithotripsy. With existing probes, users must rely on gross motor control to perform the procedure. For example, to adjust the length of a probe disposed in a bodily passage, a user must either manipulate the firing handle or grasp a portion of the probe itself, which is smooth and relatively small. The lack of fine motor control over the probe while performing lithotripsy decreases the efficiency of the procedure and increases the likelihood of the probe perforating the wall of the bodily passage and/or causing tissue damage, especially in relatively small bodily passages.
Scopes used to perform lithotripsy generally include optics to provide visualization of the stone that is desired to be fragmented and removed from the bodily passage. However, in some cases the stone is located within, or beyond, a curve defined by the wall of the bodily passage, or is offset from the working channel of the scope. Therefore, the scope must be manipulated (e.g., pushed into the wall of the bodily passage) such that the probe can be advanced to fragment the stone, which can result in the optics becoming obstructed by the wall of the bodily passage. This increases the complexity and time required to complete procedure because it prevents the optics from visualizing contact between the probe and the stone during treatment.
Therefore, a need exists for improved devices and methods for use in the performance of lithotripsy.